diff --git a/pkgs/by-name/bl/blitz/package.nix b/pkgs/by-name/bl/blitz/package.nix
index e5e44fddc2f2..4929a9ac66e3 100644
--- a/pkgs/by-name/bl/blitz/package.nix
+++ b/pkgs/by-name/bl/blitz/package.nix
@@ -44,6 +44,14 @@ stdenv.mkDerivation rec {
     })
   ];
 
+  # CMake 4 is no longer retro compatible with versions < 3.5
+  # cmake_minimum_required was already to an upper version, but not cmake_policy
+  postPatch = ''
+    substituteInPlace CMakeLists.txt --replace-fail \
+      "cmake_policy(VERSION 3.1)" \
+      ""
+  '';
+
   nativeBuildInputs = [
     cmake
     pkg-config